enter image description hereI see these values written on inductor symbols on the schematic of an RF filter/PA, what to make of these values?

a) what does "4T1.5D*0.31" means?

b) what does "CM" means in this expression "1uH/CM"?

c) what does "CI" means in this expression "1uH/CI"?

  • \$\begingroup\$ Impossible to say without more context. They look more like formulas or proportions than values. \$\endgroup\$
    – user39382
    May 24, 2016 at 0:20
  • \$\begingroup\$ Would you believe the second is 1 \$\mu\$Henry per centimeter? \$\endgroup\$ May 24, 2016 at 1:58

1 Answer 1


The first one is instructions for constructing a coil: 4 turns, 1.5 inches(?) diameter, 0.31 long.

CM may mean comon-mode, but I don't know what CI would be.


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